手法を比較

	Blockmodeling	Positional Analysis	Triad Census
分野	Sociology	Sociology	Sociology
系統	Process / pipeline	Process / pipeline	Process / pipeline
提唱年	1976	1976	1970
提唱者	Harrison White, Scott Boorman & Ronald Breiger	Harrison White, Ronald Burt, and colleagues	Paul Holland & Samuel Leinhardt
種類	Network partitioning into positions and a reduced role structure	Framework for identifying network positions and the roles among them	Enumeration of the 16 isomorphism classes of directed triads
原典	White, H. C., Boorman, S. A., & Breiger, R. L. (1976). Social structure from multiple networks. I. Blockmodels of roles and positions. American Journal of Sociology, 81(4), 730–780.	Burt, R. S. (1976). Positions in networks. Social Forces, 55(1), 93–122.	Holland, P. W., & Leinhardt, S. (1970). A method for detecting structure in sociometric data. American Journal of Sociology, 76(3), 492–513.
別名	block modeling, blockmodel analysis, generalized blockmodeling, CONCOR	role analysis, positional role analysis, network role and position analysis, regular equivalence analysis	triad count, triadic census, 16-type triad census, MAN triad census
関連	4	5	4
概要	Blockmodeling is a family of methods that simplify a social network by partitioning its actors into positions — groups of actors who are equivalent in their pattern of ties — and summarizing the relations between positions as a compact image, or reduced role structure. Introduced by Harrison White, Scott Boorman, and Ronald Breiger in 1976, it shifts attention from individuals to the structural roles they occupy.	Positional analysis is the network-analytic program that identifies the positions actors occupy — sets of actors equivalent in their relational patterns — and characterizes the system of roles that links those positions. Growing out of Harrison White's structuralism and Ronald Burt's operationalization in the 1970s, it treats the social structure as a small set of positions and the role relations among them, rather than as a collection of individual actors.	The triad census counts how many of a directed network's three-actor subgroups fall into each of the 16 possible types of triad, providing a compact fingerprint of the network's local structure. Introduced by Paul Holland and Samuel Leinhardt in 1970, it is the standard way to test structural theories — balance, clustering, transitivity, ranked clusters — by comparing the observed distribution of triad types against what a random network would produce.